Complications

Left untreated, an arteriovenous fistula can cause complications, some of which can be serious. These include:

• Heart failure. This is the most serious complication of large arteriovenous fistulas. Blood flows more quickly through an arteriovenous fistula than it does through normal blood vessels. As a result, your heart pumps harder to make up for the increase in blood flow. Over time, the increased workload on your heart can interfere with how the heart works, leading to heart failure.
• Blood clots. An arteriovenous fistula in your legs can cause blood clots to form, potentially leading to deep vein thrombosis, a painful and potentially life-threatening condition if the clot travels to your lungs (pulmonary embolism). Depending on where your fistula is, it can lead to a stroke.
• Leg pain. An arteriovenous fistula in your leg can cause pain in your leg (claudication), or can worsen pain you already have.
• Bleeding. Arteriovenous fistulas may lead to bleeding in your gastrointestinal system.